Method and means for contacting finely divided solid particles with fluids



Dec 3, 1945 L. c. HUFF 2,412,152

METHOD AND MEANS FOR CONTACTING FINELY DIVIDED SOLID PARTICLES WITH FLUIDS Filed oct. 29. 1943 I Wnemzr 3 NBER UNITED sTATEs PATENT OFFICE METHOD AND MEANS lFOR. CONTACTING NELY DIVIDED SOLID PARTICLES WITH UIDS Lyman CJluft, Chicago, Ill., assignor to Universal Oil Products Company, Chicago, Ill., a corporation of Delaware Application October 29, 1943, Serial No. 508,114

8 Claims. (Cl. 196-52) 2 This invention relates to an improved method ing zone, reversing the direction of now of said and means for contacting nely divided solid parsolid particles by admixing them with a vertically ticles with fluids and in particular to a. method upward flowing stream of gaseous fluid to be conand means for conducting various hydrocarbon .tacted in the upper contacting zone. Passing the conversion reactions in which vapors or gaseou" resultant suspension vertically upward into the hydrocarbons are contacted with finely divided lower portion of said upper contacting zone Wheresolid catalyst particles. in the upward velocity of the gaseous iluid will The present invention may be advantageously cause the maintenance of a lower dense solid parapplied to various hydrocarbon conversion reacticle gaseous fluid phase and an upper relatively .tions in which catalysts are employed, such as 10 dilute solid particle gaseous iiuid phase, contincracking, dehydrogenation, aromatization, alkylaually passing solid particles from the dense phase tion, reforming, and the like. in the upper contacting zone into the upper p0r- In the various hydrocarbon conversion proction of the lower contacting zone, thereby mainesses coming within the scope of this invention, taining a continuous downward flow of solid palthe catalyst particles during their contact with ticles therethlOugh withdrawing gaseous lluid the reactant materials gradually become inactive from the dilute phase in the upper contacting due to the accumulation thereon of deleterious Zone, and passing a SeCOnd gaseous fluid through deposits. These deposits are hydrocarbonaceous the lower contacting Zone in contact with the in nature and are generally removed by combus- S0lid particles therein.

tion with air to restore the catalyst to a useful In the 'process of the present invention only activity. one high velocity stream of mixed iluid and solid In order to maintain continuous processes for particles 1S employed and this stream moves in these various reactions, it is necessary to main-v a single direction without bends or turns which tain a continuous cyclic now of catalyst particles might become erOded due t0 the abrasive action between the reaction zone and the combustion of the catalyst particles. The remainder of the or regeneration zone. severa] methods are now transfer system carries streams of relatively low in use in the industry for accomplishing .this Velocity and alSO ln a Substantially uni-direcv transfer of catalyst particles between .the two tlonalflOW Without turns 01 bendsmain zones of the process. For instance, in some In order to further illustrate the additional processes conveyors and bucket elevators are emfeatures and advantages of the invention, referployed, while in others gases or iiuid carriers are ence is made to the accompanying diagrammatic used. However, in all known installations, a high drawing and the following description thereof.

degree of erosion of equipment and attrition of Figure 1 0f the drawing illustrates in sectional v catalyst particles is now encountered. eleVatiOn One particular type of equipment in The present invention oii'ers means for substan- 35 which the process of the invention may be actially overcoming these two difficulties -by a new complished. and novel method. Figure 2 is an enlarged view of the lower end of Broadly, the present invention comprises a' the transfer conduit which forms a part of the method of transferring nely divided solidv par- 4equipment ShOWn in Figure 1- ticles from a lower zone to a higher zone by con- 40 The apparatus here illustrated comprises a tinuously passing said solid particles vertically vertically elongated shell l closed at its upper downward from said lower zone, reversing the diend by head 2 and at its IOWer end by a ironically rection of flow of said solid particles by admixing Shaped head 3. 'I'he shell is divided into two zones them with a vertically upward flowing stream of by means of a partitioning member 4 which is fluid. and passing the resulting vertically upward Secured t0 the interior 0f Shell l by Welding 0r flowing suspension of solid particles and iiuid into Other Suitable means- Spaed from IOWer head 3 said higher zone. is a perforate distribution member 5, the purpose In a more limited embodiment, the present in- 0f Which Will be hereinafter described. vention comprises a method of contacting finely Extending downwardly from head 3 is an divided solid particles successively with two gaseelongated conduit 6 which terminates in a closous iiuids, which comprises maintaining two solid ure member 1; Disposed centrally within shell I particle gaseous uid contacting zones in vertical and extending from adjacent member 'l through alignment and partitioned from each other, conpartition member 4 is a transfer conduit 8. Continuously passing solid particles vertically downduit 8 is supported within conduit 6 by means of ward from the lower portion of the lower contact 55 suitable brackets 9 which are secured by welding or other suitable means and the upper end of vconduit 8 is secured to partition member 4. To

' plurality of pistons I5, fluid for motivating pistons I is supplied and withdrawn through conduits I1 and I8, headers I9 and 20, and branch conduits 2l and 22. By supplying nuid through conduit I'I and withdrawing tluid through conduit I8, slide I4 will be moved downwardly to restrict the fiow of solid particles from conduit 6 into conduit 8, and by removing fluid through conduit I1 and introducing fluid through conduit I8 and slide I4 will be raised, thus opening the way for a greater iiow of solid particles from conduit 6 into conduit 8.

To further illustrate the utility of the invention, its operation when employed for conducting a catalytic cracking reaction will now be described.

A- moving body of catalyst particles, I4, is maintained in the lower contacting zone by continuously withdrawing some of said particles through conduit 6, the rate of withdrawal being regulated by means of slide I4. The withdrawn catalyst particles are then commingled with a stream of regenerating gases introduced through conduit 23 controlled by valve 24. 'I'he resulting solid particle gas suspension then passes through conduit 8 into the upper contacting zone I3. The upward velocity of the regenerating gasv in zone I3 is such that two solid particle gas phases are formed and maintained. The lower phase is relatively dense having a cracking catalyst content of as much as or 25 pounds per cubic foot. The upper extent of this dense phase is indicated by line 25. In the upper or light phase above the interface indicated by line 25, the catalyst concentration is sometimes less than one pound per cubic foot.

'I'he eiiluent combustion products from the upper contacting zone pass through separator 26 wherein suspended catalyst nes are removed and the catalyst-free gases are withdrawn through A line 21 controlled by valve 28 to be directed to suitable waste heat recovery equipment. The removed catalyst fines are returned to the dense zone by means of conduit 29.

In order to maintain a continuous flow of catai lyst through the lower contact zone regenerated catalyst particles are continuously withdrawn from the dense phase in the upper zone by means of conduit 30 controlled by valve 3l. A suitable stripping medium such `as steam or inert gases may be introduced to conduits 6 and 80 by means of lines and 32 controlled by valves 4I and 33 respectively. f

The hydrocarbon charge, preferably in vapor form, is introduced to the system by means of conduit 84 controlled by valve 85 and enters the chamber between head 3 and distribution member 5. The charging material will pass through the perforations in member 5 and contact the catalyst in zone I4 to accomplish the desired reaction. I'he eilluent reaction products pass through cyclone separator 8S wherein suspended fine particles are removed and returned to the system by means of conduit 31, the catalyst-free reaction products are then withdrawn through 4 conduit 38 controlled by valve 88 to be directed to suitable fractionation and recovery equipment as desired.

It can be seen from the above description that the catalyst particles pass in a continuous cyclic flow through the system. The catalyst particles pass through the reaction zone to accomplish the desired reaction and accumulatl the resulting carbonaceous deposit, then are withdrawn and transported into the regenerator where the carbonaceous deposit is removed by combustion. The reactivated catalyst is then transferred from the regenerator to the reactor to complete the circuit.

Suitable catalyst and operating conditions for the various processes which come within the scope of the invention have not been described in detail herein because they are well known in the art.

I claim as my invention:

1. A method of contacting finely divided solid particles successively with two uids which comprises maintaining two solid particle uid contacting zones in vertical alignment and partitioned from each other, continuously passing solid particles vertically downward in anannular column from the lower portion of the lower contacting zone, reversing the direction of ow of said solid particles by admixing them with a vertically upward owing stream of iluid to be contacted in the upper contacting zone, passing the resultant mixture upwardly in straight line ilow in a confined path extending vertically through said annular column and said lower zone, thereafter discharging said mixture into the lower portion of said upper contacting zone wherein the upward velocity of said iluid will cause the maintenance of a lower dense turbulent solid particle liuid phase and an upper relatively dilute solid particle iluid phase. continuously passing solid particles from the dense phase in the upper contacting zone into the upper portion of the lower contacting zone, thereby maintaining a continuous downward flow of solid particles therethrough, withdrawing iluid from the dilute phase in the upper` contacting zone and passing a second fluid through the lower contactingv zone in contact with the solid particles therein.

2. A process for the catalytic conversion of hydrocarbons which comprises maintaining two vertically aligned separate contacting zones, maintaining the lower of said contacting zones at conversion conditions and maintaining the upper of said contacting zones at regeneration conditions, moving a compact bed of finely divided catalyst particles downwardly through the lower contacting zone, continuously withdrawing said catalyst particles vertically downward in an annular column from the lower portion of said lower contacting zone in a vertically downward direction, reversing the direction of ow of said withdrawn catalyst particles by admixing them with a vertically upward flowing stream of regenerating gases, passing the resulting suspension upwardly in straight line flow in a coniined path extending vertically through said annular column and said lower zone, thereafter discharging said suspension into the upper contacting zone wherein the upward velocity of the gases will cause the maintenance of a lower dense turbulent catalyst particle gas phase and an upper relatively dilute catalyst particle gas phase, continuously passing catalyst particles from said dense phase into the upper portion of the lower contacting zone, withdrawing combustion products from said dilute phase, passing hydrocarbons into and through the lower contacting zone in contact with the catalyst particles moving therethrough, and withdrawing reaction products from said lower contacting zone.

3. A method for contacting a subdivided solid successively with two fluids which comprises maintaining a bed of subdivided solid particles in each of two contacting zones disposed in vertical alignment,'passing one of said fluids through the bed in the lower of said zones, continuously discharging solid particles from the upper of said zones onto the top of the bed in said lower zone and withdrawing solid particles vertically downward in an annular column from the lower portion of said lower zone, thereby maintaining a downward movement; of the solid particles of the bed in the lower zone, reversing the direction of ow of the particles withdrawn from the lower zone by commingling the same with a vertically upward iiowing stream of the other of said iiuids,`

passing the resultant mixture upwardly in straight line ilow in a coniined path extending vertically through said annular column and the bed in said lowerzone and then discharging the same into the lower portion of the upper zone at sufcient, velocity to maintain the bed in the lastmentioned zone in turbulent condition.

4. A process for the catalytic conversion of hydrocarbons which comprises maintaining a bed of subdivided solid catalyst particles in a lower reaction zone and in an upper regenerating zone disposed in vertical alignment, passing the hydrocarbons at conversion temperature through the catalyst bed in the lower reaction zone, continuously discharging regenerated catalyst particles from the upper regenerating zone onto the top of the catalyst bed in the reaction zone and withdrawing contaminated catalyst particles vertically downward in an annular column from the lower portion of the reaction zone, thereby maintaining a downward movement of the catalyst particles of the bed in the reaction zone, reversing the direction of ow of the particles withdrawn from the reaction zone by commingling the same with a vertically upward flowing stream of oxygen-containing regenerating gas, passing the resultant mixture upwardly in straight line ilow in a conned path extending vertically through said annular column and the bed in the reaction zone and then discharging the same into the lower portion of the regenerating zone at suflicient velocity to maintain the bed in the lastmentioned zone in turbulent condition, and burning carbonaceous matter from the catalyst particles forming the turbulent bed in the regenerating zone.

5. An apparatus of the class described comprising a vertically elongated shell, partitioning means dividing the shell into an upper contacting zone and a lower contacting zone, means for maintaining a bed of solid particles in each of said zones, uid inlet and outlet means for said lower zone, a discharge conduitfor solid particles extending vertically downward from the bottom of said shell and communicating with said lower zone, an open-ended vertical conduit extending from the lower portion of said discharge conduit through the lower contacting zone and said partitioning means into the upper contacting zone, a fluid inlet at the lower end of said discharge conduit and in communication with said open-ended conduit, a second open-ended vertical conduit disposed in said shell out of alignment with the iirst-named open-ended conduit and extending from a point within the upper contacting zone through said partitioning means into the upper portion of the lower contacting zone, and means for removing fluid from said upper zone.

6. In the catalytic conversion of hydrocarbons wherein a stream of the hydrocarbons is contacted under conversion conditions with subdivided solid catalyst particles in a contacting zone and resultant contaminated catalyst particles contacted with a stream of oxygen-containing gas under combustion conditions in a separate contacting zone disposed in vertical alignment with respect to the first-named' contacting zone, the method which comprises transferring catalyst particles from the upper to the lower of said contacting zones, withdrawing catalyst particles vertically downward in an annular' column from the lower portion ofv said lower zone, simultaneously passing one of said streams upwardly in straight line ilow in a 4confined path extending vertically through said annular column and said lower zone, suspending the catalyst particles of said annular column in said upwardly ilowing stream, and discharging the resultant suspension from said confined path into said upper contacting zone.

7. The method as defined in claim 6 further characterized in that the hydrocarbons are contacted with the catalyst particles in said lower zone and in that the stream of oxygen-containing gas is passed upwardly in said conned path and then into the upper contacting zone.

8. An apparatus of the class described comprising an upper contacting chamber and a lower contacting chamber disposed i'n vertical alignment, means for lmaintaining' a bed of solid particles in each of said chambers, fluid inlet and outlet means for said lower chamber, a discharge well for solid particles extending downward from the lower end of said lower chamber, an openended vertical conduit extending from the lower portion of said discharge well through the lower contacting chamber' into the upper contacting chamber, a iluid inlet at the lower end oi said discharge well and in communication with said open-ended conduit, a second open-ended vertical conduit connecting said upper chamber with said lower chamber and disposed out of alignment with the rst named open-ended conduit and extending irom a point within the upper contacting chamber into the upper portion lof the lower contacting chambenand means for removing fluid from said upper chamber.

LYMAN C. HUFF. 

